RE: Differential incremental backups

I read him as asking something nobody is picking up on. As I read his
concern it says regardless of type of backup, if the level 0, or
whatever base is taken on Sunday, March 14th, and he has archives for
the entire month of march, can he recover to Friday March 12th. For
the sake of the example he does not have another base backup supporting
Friday, March 12th.

Orlando can confirm if this isn't the actual question. Of course as
with all backup scenarios, as Jared pointed out, one should test it
regardless of whether you believe you have the answers or not.

Thanks. I wonder how it can restore to previous Friday if a base backup
gets taken Sunday night. I thought it would restore base backup first
and then apply incremental on the top of that base backup. I thought
the backups taken before base backup were useless and cannot be used to
restore to a point in time in last week, even if recovery window of 7
days is specified. ie, in this example, wanting to go back to last
Friday on a given Monday, with a base backup on Sunday.

Also keep in mind that RMAN automatically manages retentions for you,
so if you tell it that you need to have a retention policy of 'RECOVERY
WINDOW 7 DAYS', it will automatically keep all the backup files required
to guarantee that policy. You will also have to use RMAN commands to
ensure backup consistency when deleteing files (namely: delete
obsolete).

differential and comulative are exclusive to each other, but each of
them is incremental backup.

Orlando, if you want recover your database till some <recover_point>,
you should have available all incremental backups until recover_point
and all archived logs between start_time of last incremental backup and
recover_point

2010/3/18 William Muriithi <william.muriithi_at_epicadvertising.com>

First, you said differential incremental backup. I believe
differential and incremental are exclusive to each other if I am not
wrong.

Now assuming incremental, you use the monday full backup and all
incrementals up to Thursday.

If its differential, you use the full backup and the last
differential backup, which is Thursday